Weingart, W. (1910), Cereus regelii Weing. sp. n. Monatsschrift für Kakteenkunde 20: 33 [tax. nov.]

Backeberg, C. in Backeberg, C. & Knuth, F.M. (1936), Kaktus-ABC, en Haandbog for Fagfolk og Amatorer: 178 [basionym]

basionym of: Eriocereus regelii (Weing.) Backeb. legitimate

Borg, J. (1937), Cacti. A Gardener's Handbook for Their Identification and Cultivation: 145 [basionym]

basionym of: Harrisia regelii (Weing.) Borg legitimate

Ross, E.M. in Stanley, T.D. & Ross, E.M. (1984), Cactaceae. Flora of South-eastern Queensland 1: 144 [nomenclatural synonym]

nomenclatural synonym of: Eriocereus regelii (Weing.) Backeb. legitimate

Leuenberger, B.E. (2000), Harrisia regelii (Weingart) Borg and the discovery of its Argentinian origin. Haseltonia 7: 90 [secondary reference]

Leuenberger, B.E. (2000), Harrisia regelii (Weingart) Borg and the discovery of its Argentinian origin. Haseltonia 7: 90 [nomenclatural synonym]

nomenclatural synonym of: Harrisia regelii (Weing.) Borg legitimate

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